Last Thursday, 25 year-old Sun Danyong committed suicide after a fourth-generation iPhone prototype he was responsible for went missing. It's a story, from what tech-industry friends in China tell me, of how Apple's secretive ways send extreme pressure all the way down the company's international supply chain.

On Thursday, July 9th, Sun got 16 prototype phones from the assembly line at a local Foxconn factory. At some point in the next few days, he discovered that one of the phones was missing. He suspected that it had been left at the factory, but couldn't find it. On Monday, July 13, he reported the missing phone to his boss.

Then, that Wednesday, three Foxconn employees searched his apartment — illegally, according to Chinese law. Accusations are flying that Sun was detained and physically abused during the investigation, although this has not been substantiated (possible evidence: there's this somewhat garbled and potentially faked instant message exchange from Sun shortly before his death).

Taiwan-based Foxconn makes Apple's iPhones and iPods, along with numerous other hardware devices for other international technology companies. It faces cutthroat competition from other manufacturers around China and the world. A leak of the next generation of Apple's crown jewel, the iPhone, could badly hurt Foxconn's business relationship with Apple.